#include<stdio.h>
int gcd(int a, int b)
{
	if (b == 0)
		return a;
	else
	return gcd(b, a % b);
}
int main()
{
	int c, d;
	scanf_s("%d%d", &c, &d);
	int m = gcd(c, d);
	printf("%d\n", m);
	return 0;
}